By Ron Marshall
Robert, the plant manager, was puzzled. His compressed air system had been running smoothly, but his energy bills seemed high. After reviewing his equipment, he realized the issue was the compressor’s cycle time.
In a typical compressed air system, a lubricated screw compressor operates in load/unload mode. The cycle time refers to how long it takes for the compressor to go from loading (pressurizing) to unloading (releasing pressure). The faster the compressor cycles, the more energy it consumes, even if the output remains constant.
To understand the impact of cycle time on efficiency, Robert performed a simple test. He timed how long it took for his compressor to load and unload. After measuring several cycles, he noticed the cycle time was under one minute. According to industry best practices, cycle times shorter than one minute mean the compressor is running inefficiently. A longer cycle time, ideally more than two minutes, can significantly reduce energy consumption.
The challenge, however, was that many facilities, just like Robert’s, don’t have tools to measure or visualize these cycles in a meaningful way. That’s where Compressed Air Challenge (CAC) training comes in.
Unlike standard training programs, CAC offers charts that illustrate the relationship between cycle time and energy efficiency, including the impact of system components like storage receivers. These charts aren’t typically found anywhere else. For example, the ideal receiver capacity should be 5 gal per cfm or more, with the largest compressor in mind, not the total system capacity.
The charts show adjusting the pressure band (e.g., increasing it from 10 to 20 psi) can halve the cycle time and increase overall system efficiency. Other factors, like pressure drops due to undersized piping or excessive dryer and filter losses, can also cause excessive cycling, these solutions are covered in depth during the CAC’s hands-on training.
Robert now knows that by addressing these cycle time factors, he can optimize efficiency and significantly reduce his plant’s energy costs, thanks to the exclusive insights he gained from the Compressed Air Challenge training. Check out the next training session by visiting the calendar here: www.compressedairchallenge.org/calendar
